The artificial placenta: SCI-FI or reality?

An artificial placenta is a life support platform for babies born preterm, or prior to 37 weeks’ completed gestation. Although there is potential to use this platform for the intraoperative repair of congenital abnormalities (e.g. congenital diaphragmatic hernia) in late preterm babies, or for the study of fetal development, the primary target for this technology is currently treatment of extremely preterm infants, or those delivered during the peri-viable period between 21-24 weeks’ completed gestation. Babies born in this peri-viable period generally have poor outcomes due to the need to mechanically ventilate their extremely immature lungs–often at high peak pressures. Artificial placenta-based life support platforms are designed to obviate the need to ventilate as a means of facilitating gas exchange, and thus avoid injury to the immature preterm lung. Instead, highly efficient, and easily regulated gas exchange is performed by gas-exchange devices connected to the fetal vasculature. Depending on the form of the system used, venous-venous and arterio-venous circuit designs have been trialled, with the more recent arterio-venous prototypes using the fetal heart, rather than an external pump, to generate circuit pressure. Despite having the appearance of a futuristic concept, work to develop an artificial placenta has been undertaken intermittently since at least the late 1950s. That the technology is yet to enter clinical service, despite 60-plus years of work, reflects the technical challenges surrounding the development and use of the artificial placenta. This delay in introduction also reflects the changing neonatal care landscape, and notably advances in mechanical ventilation and non-invasive respiratory support modes such as continuous positive airway pressure, the introduction of antenatal steroids, and the availability of exogenous surfactant therapy. As such, it is reasonable to argue that the target demographic for artificial placenta technology has cha